A new analysis of a photograph taken by NASA’s Cassini spacecraft reveals an unusually bright light amid the frozen seas of Saturn’s giant moon Titan. But according to researchers from the University of Idaho in Moscow, the light — just a few pixels in the overall image — is no alien transmission or nuclear blast but a reflection of the planet’s churning waters: It’s the first time waves on the seas of the moon have been spotted.

“If correct this discovery represents the first sea-surface waves known outside of Earth,” wrote Jason Barnes and colleagues in apaper presented at the 45th Lunar and Planetary Science Conference.

‘If correct this discovery represents the first sea-surface waves known outside of Earth.’

– University of Idaho in Moscow researchers

Like Earth, Titan is covered with vast bodies of liquid, as well as islands splashed by rain clouds and carved into channels by rivers. The photo shows the surface of Punga Mare, one of Titan’s typically calm, flat hydrocarbon seas, disturbed by tiny ripples less than an inch high, according to researchers.

“Titan may be beginning to stir,” Johns Hopkins planetary scientist Ralph Lorenz told Nature recently. “Oceanography is no longer just an Earth science.”

Researchers suspect more waves to appear as winds pick up in Titan’s northern hemisphere with the changing seasons.

“That they have previously been undetected and are now evident is consistent with the Lorenz hypothesis that winds had previously been low due to seasonal cycles but are picking up as northern spring develops,” the researchers wrote.

Understanding how the waves form will help shed light on Titan’s eery waters. On Earth, oceans churn and foam in liquid form; Titan has a surface temperature of -290 degrees Fahrenheit, meaning its waters are largely frozen.